Restricted Chemical Screening Protocols for Unfinished Woven and Knitted Substrates
Unfinished woven and knitted substrates carry sizing biocides, needle oils, and surfactants that require selective solvent extraction to prevent border seizures.
Circular Knits
Structural Geometry
Continuous tubular loops interlocked on rotating needle beds form seamless fabric structures across automated knitting cylinders. Secondary processing converts circular knits into flat yardage by slitting the tubular length along a needle line prior to stentering and heat setting. The continuous spiral courses created during circular knitting produce an inherent skew known as spirality, which affects grainline alignment in finished garments.
Garment manufacturers evaluate course density and wale density to calculate total fabric weight and dimensional stability.
Machine Configuration
Needle cylinders equipped with multiple yarn feeds determine the structural capability and production rate of the knitting machine. Single jersey machines utilize one set of latch needles to produce asymmetrical face and back surfaces, whereas double jersey machines employ cylinder and dial needle arrangements. Feed count variations impact spirality angles and yarn tension across the circular knitting frame.
Precise yarn feeding mechanisms prevent uneven loop lengths that cause horizontal banding across the knitted tube.
Fabric Distortion
Torque applied to spun yarns during loop formation causes the knitted courses to slant away from a perpendicular alignment. Slitting tubular fabric relieves internal strain but exposes edge curling tendencies caused by asymmetric loop tension. Relaxed washing and tumble drying release residual mechanical stress, shifting the wale lines into a permanent resting position.
Garment patterns cut from unrelaxed fabric suffer from twisted seams and asymmetric panel deformation after laundering.
Commercial Specification
Purchase orders specify finished weight per unit area along with maximum allowable spirality percentage and dimensional change limits. Inspection facilities verify these parameters using standardized wash testing.